Re: Possible regression due to "net/sched: cls_flower: Add offload support using egress Hardware device"

On Sat, Dec 03, 2016 at 06:06:08PM +0200, Or Gerlitz wrote:

On Sat, Dec 3, 2016 at 3:17 PM, Simon Horman [off-list ref] wrote:

quoted

in net-next I am observing what appears to be an regression in net-next due to:
7091d8c7055d ("net/sched: cls_flower: Add offload support using egress Hardware device")

The problem occurs when adding a flower filter (without offload to a virtio device).

quoted

# ethtool -d eth0
ethtool -i eth0
driver: virtio_net

quoted

# tc qdisc add dev eth0 ingress
# tc filter add dev eth0 protocol ip parent ffff: flower indev eth0
[  104.302779] BUG: unable to handle kernel NULL pointer dereference at 00000000000000d5

Simon, I don't see an action here, is that missing in purpose? wasn't
sure what such filter does, but ofcourse
if it was supported by the patches it has to be so after changing
things as well, we will check and fix.

Hi Or,

sorry, I trimmed the action by mistake when trying to make a minimal test
case. Originally I noticed this bug with something like the following:

tc filter add dev eth0 protocol ip parent ffff: flower indev eth0 ip_proto udp dst_port 53 action drop

I don't think the fields flower is matching on or the action are
particularly important when trying to reproduce the problem. But I could be
wrong.